Which rail pass and how to get to venice?

The Swiss Half-Fare Card for one month ($126 per adult) will certainly save money over full-fare tickets but the Swiss Travel Pass for 4 consecutive days ($284 per adult) would be my preference if you'll really take all the side trips you mention.

Travel from Luzern to Venice via Chur and Tirano takes 12 or 13 hours. If you depart Luzern at 8:30, you'd be at Pontresina at 13:00, in Varenna on Lake Como at 16:40 (recommended overnight location), Milan at 17:40, or Venice at 20:40. Similar timing with departure at 9:30 or 10:30. I wouldn't mind the long train day but it might not be your preference as a family. Of course, there are lots of hotels near Milan train station, too, but it's not a cheap city.

P.S. There's no particularly special scenery on the main line from Milan to Venice, if you were concerned about hours of daylight.

From Lucerne to Venice takes 6 to 7 hours by train. [Oops--that's the direct route. The scenic route taken by the Bernina Express takes much longer. Ignore me!]

Where are you landing in Europe, and how are you getting to Lucerne to begin your stay in Switzerland?

It's unclear how much time you have for Italy, but I question traveling all the way to Venice and then staying only one or two nights. Even two nights there means just a bit more than one day in Venice. That's not much of a visit.

Luzern to Veniceis 6-7 hours if you take the direct route to Milan. In the Gotthard Base tunnel, which is a very long tunnel under the Alps.

They wish to take the scenic Bernina route over the Alps, which takes longer but is well worth it. We did this a. Opulent of years ago and really enjoyed it. We had extra time before Venice so spent two nights in the Engadine on the Bernina route, then one night in Varenna.

For their time frame, I agree with Laura’s suggestion to spend the night in Varenna.

Note that you can take regular regional,trains, which run hourly on the Bernina Pass route. It does not have to be the named “Bernina Express”.

Lucerne as base. From there we plan on going to take Golden Pass, Berner Oberland, Bern-Murten via train.

I am not sure what you are referring to here. The "Golden Pass route" is Luzern - Interlaken - Zweisimmen - Montreux. If you are doing this as a day trip from Luzern, you will have to double back.
If you look up "Luzern - Montreux" (or vice-versa) on the Swiss Railways site ( https://www.sbb.ch/en ) it will give you the quicker but longer route via Bern and Lausanne. If you want the Golden Pass route, you need to add "via Zweisimmen".

The Berner Oberland is an area of Switzerland, the area around Interlaken, not a rail route.

I have never seen Bern-Murten being in a list of scenic rail routes. It is not a mountain route, it is in the Swiss lowlands.

Don't forget all Swiss rail lines have at least one train per hour, so you have plenty of choice.

You can see all these routes (and the Bernina route) on the Swiss rail map here: https://www.sbb.ch/content/dam/infrastruktur/trafimage/karten/karte-sts-pass-gueltigkeit.pdf

Thank you all for great replies.

Sorry, I forgot to mention that we are going in March. Why March? Family wedding in Manchester. Since, we are coming all this way and taking our son out of school, why not take advantage and travel. We may not come back until next wedding as its really expensive. We were here (Switzerland) last in 2005.

I really wanted to spend time in small town in Alps but not in cold winter in March.

We are spending two nights in London, 3 in Manchester, 2 in Amsterdam then we fly in to Zurich. Then 3 nights in Italy. One more in London and back to So Cal.

I've been reading Rick's book on what to do in Switzerland. Last time we came we didn't have oru son and didn't know Rick's book existed.

Thanks again,
Paresh

Sorry, I forgot to ask. Should I buy Swiss travel pass from AAA or some other local agent or directly from Swiss rail website?

Where does your trip start in Switzerland? They are sold in staffed train stations such as Zurich airport or Luzern.

If you're choosing a consecutive-day variety, they can be printed at home, since they don't really want longer lines in train stations. These come prevalidated for a specific window of travel time. You can buy them through us or through SBB.ch (under international visitors). I don't think AAA would provide any benefit in this case.

A one-month Half-Fare Card can also be printed at home, but our shopping cart doesn't add the free Family Card in that case; you would have to pick it up in a station.